Brush-tripping device



Nov. 6, 1923.

1,472,818 L. R. WALLER BRUSH TRIPPING DE-VICE Filed Dec. 2, 1920 2 Sheets-Sheet 1 ma Vf Nov. 6 1923. 1,472,818

L. R. WALLER BRUSH TRIPPING DEVICE Filed Deo. 2. 1920 2 Sheets-Sheet 2 Lee ,i wa/ler.'

Patented Nov. 6, 1923.

UNITED STATES PATENT OFFICE.

LEE R. WALLER, OF WESTMOUNT, QUEBEC, CANADA,

ASSIGNOR T0 WESTERN ELEC- TRIC COMPANY, INCORIORATED, OF NEW YORK, N. Y., A CORPORATION 0F NEW YORK.

Application led December 2, 1920.

To all whom it may concern:

Be it known th at I, LEE ll. Wannen, a citizen of the United States, residing at l/Vestmunt, in the Province of Quebec and Dominion of Canada, have invented certain new and useful Improvements in Brush- Tripping Devices, of which the following is a full, clear, concise, and exact description.

This invention relates to automatic and semi-automatic telephone exchange switching apparatus andy more specifically to devices for,tripping the contact brushes of selector and connector switches.

The object 'of the invention is the provision of asimple and'reliable mechanism which will operate; automatically to trip a Set of brushes without involving the use of electromagnets.

The invention is set forth in connection witht a switch of the wellknown panel type but its application is not limitedtc switches of that articular type.` ,1,

:The' ndamfen'tal feature vor' the invention. as well yas tsmore specific features can best be setforth by means oi a detailed description 4V,of the mechanismand its operation. Before enteringinto such a detailed description, however, it is thought best to give abrief general description of a panel e selector switch;

The paneltype selector switch is so called because of the fiat panel like terminal bank.

which is employed in connection therewith. The` faces of the bank are situated vertically and stationary contact. terminals are provided on both sides thereof. Theterminals are arranged ,in vertical. rows, each row consisting usually; of, five hundred sets of terminals. These rows aremultipled horizontally acrossthe face of the bank.-

, A' bank isv ordinarily ,divided intove individual ,sections rwhich are. arranged in superimposed relation one to the other. there are Va total of five hundred sets of termixials, in'each vertical row there would` then, be one hundred sets in each row of each section-` v Associated with each vertical row of terminals on the bank is a, vertical brush rod which` is adapted to be moved up and down. There are live sets ofcontact brushes attached to each brush rod andada ted to be moved up and down therewith. ach brush et is associated with the contact terminals in one section, that is one hundred terminals.

Serial N0. 427,850.

The brush sets are all normally held under tension in such a manner that they will not engage the bank terminals when moved thereover.

The brush rods together with the brush sets mounted thereon normally stand in their lowermost positions. Means are provided for elevating the brush rod when it is desired to establish a connection between one of the brush sets and a set of bank terminals. Means are also provided for lowering the brush rod, i. e. restoring it to normal. When a call is to be extended through a particular selector switch, an idle brush rod, that is one standing in its normal position is selected. One of the brush sets must then be released to permit it to engage its associated bank terminals, the other brush sets being left in their normal positions. The brush set to be selected depends upon which section of the bank contains the terminalsof the desired line. After the selected brush set is released the brush rod moves up until the desired terminals are engaged whereupon the brush rod is immediately stopped. No further movement takes place until the communication is com pleted when the brush rod is moved down-` ward to its normal position and the selected brush set is also restored to normal.

This invention concerns onlythe releasing of the selected brush set. The operation of releasing the brushes is more commonly termed tripping the brushes and that expression will be used hereinafter.

In the accompanying drawings, ,three separate embodiments of the invention are shown. Figure 1 is a partial sectional view of a panel type selector switch; Figures 2, 2, 2", 2 and 2d illustrate the operation o that embodiment of the invention shown in Figure 1; Figure 3 is an enlarged sectional view taken on the line 3--3 of Figure l, showing a brush set in detail; Figure 4 is a perspective view of the tripping device of igure 1; Figure 5 is a perspective view illustrating a secon embodiment of the invention: Figures 6, 6, 6b and 6 illustrate the operation of that embodiment of the invention shown in Figure 5; Figure 7 is a perspective view of a third embodiment of the invention and Figures 8, 8*, 8 and 8 illustrate the operation of the last mentioned embodiment.

In Figure l there is shown mounted on the vertical brush rod lll. two sets of i-onlact brushes 1l. As previously' slalerl there arc ordinarily five. sets of brushes mounted iu each brush rod. 'llie brush rod and brushes. are movable vertically liv means of the coustzinllv rotatingr rollers l2 and lil. thc former operatingY lo move flic brush rod iluwn wardlv. and the lutter to more it upwardly.

Eleflro-nuignel l'l when energized draws up its armature l5 therebi pressing roller 16 against brush rod l0. and the latter in turn,y against driving roller lil. The brush rod moves upwardly as long as magnet 14 remains energized. Energization of electromagnet 17 likewise operates to effect downward operation of the brush rod.

Referring to Figure 3. it will be noted that each brush set 11 comprises four brushes arranged in pairs, the' two inner brushes 11 forming one pair, and the two outer brushes 112 formingr the other pair. Each brush 11 is mechanically connected to a brush 11z by an insulating separator 11. Brushes 11 are normally held apart against theirown tension by the insulatingr rollers 18. Brushes '112 are also normally pushed outwardly'by brushes 11 due to the separators 11. When the brushes are thus held apart they may be moved vertically over the' terminals 19 of the tank 20 without engaging those terminals. The insulating rollers 18.l are mounted on carriage 18 which is pivotedlon pin 18` A trigger 18 is inte gral with carriage 18. A downward movement of the trigger will rotate carriage 18 about its pivots and cause the rollers 1252 to be withdrawn from the position shown in F ig'ure 3perinitting the ends of the brushes to move toward each other and engage the terminals 19.l l

To extend a connection one of the several brush sets is selected and tripped. and the selected brush se't is moved over the row of terminals 19 until it engages the desired set of terminals whereupon the brush rod is stopped.

Associated with each set of brushes there is a member 21 (shown in detail in Figure 4). The members 21 are each pivoted on a pin 22 and normally .stand in the position shown in Figures 1 and 4. Each member 21 is mounted at a different lieifrht from the lowerinos't position of the en ol its associated trigger 1R', that is. when the latter are. in th ir normal positions as shown in Figure 1.

To select a brush set. the brush rod 10 is given a short preliminary upward move ment andl stopped. During the preliminary movement one or more of the triggers 1S engages the angular surface 21 of member- 21 and causes the latter lo swing'Y away from the trigger. This action is illustratedv in Figures 2 and 2. notch 212 isedapied to engage the end of the trigger 18 when the latter is stopped iu juxtaposition (hereto. following the preliminary movement as ilY lustrated iu lipigurc if". (lul'v one trigger :it a time is stopped iu juxtaposition to a uolili 212, [he remaining triggers either stopping short of. or being carried past llie noti-lies of their respectively :issoriulcrliiwinl'iirs 2l and f onsequeulliv only lhc omiriggfir is cn- ;agrefl.

lu Figure L. llie llrusil rofl luis` laii'li-il ou n secondariY movement iu Ihrv .some dircition as the prcliu'iinnrv movement. :1nd thibrusli set is being tripped. ln Figure 2" tripping of the brush set is completed.

Each member 2l swings like :i pendulum ou its pivot 22 and it may be designed lo have any desircfl period so that it will return neither too quickly nor too slowly.

When the brush rod is moved downward ly to its nolmnl position the untripped triggers will wipe over' the curved surface 2l" of members 21 and move the latter out ol the way. The tri ped trigger will not in terfere with inemlier4 21 on its downward movement. The tripped brush set is restored tolnormal when the brush rod rea clics its' lower'rnost position by the bar 24 which is adapted to engage trigger 18 when the latter is 'olf normal.

Anotherembodirent of the invention is shown in Figures 5,'6, 6d, 6b' and 6"'. bellcrank lever 25 is pivoted on pin 26 and normally stands as sli'ow'n. Another. hell-crank 27 is c'arried by the brush rod 10 :ind is pivoted ori pin 28. A vom 29 attached io hellcrarilr 27 is adapted t'o bc'acted up'onbjT air pressure to rotate the latter against' the te s'ion of r'et'rrictile spring" 30, ripon' upward movement of the' brush roel. When thus moving upwardlv, the 111327 will engage the end 25' of bell-crank- 25 rind rotate the' latter so that the end of trigger 18 will pass bellrank 2li without being errgzfagedV and tripped therel'iy. If. however, the' brush rod stops. after its" pl'jeliminarjiF movement just before the' lu'g 27 of bellcrank 27 engges the end 25 m" bell-crank 25. the latter will not be engaged by the lug 2l" upon the' secondary movement of the brush rod hec'z'ius'o the time interval required for` the lugl 27 to' pass the end 25 is shorter than `the time required for hell-crunk 27 to lie' rotated into inerl'criii; rr position b v the nir pressure actin;r on vlo 291 Tf willI li'e i'iu'derstood thatV the air pres'- surc. which .'l'cls on i'anes 29 is due to' the rapid movement of the brush rorl.

Figures 6 fo 6 inclusive illust'rfe thev se quence of operations of the lli-st described embodiment. 1in Figure n6 the brush rod is' in its normal 'position ill Figure 6 rhohrush rod hasb'oen given o preliminary movement upwardlv and stopped. In Fieure 6 bellcranlr 2l luis been 'rotatedbf.' ret'rnc'tile spring 30 inten position wherein it does not lla this case there is employed a bell-crank 31 which is pivoted on a pin 32, ay brush 33 preferably of bristles` is` carried bv the bellcrank 3l and bears against brush rod 10or A.

pin 34 on the bell-crank is adapted to interrept the path of trigger 18 when the brush rod is at rest (Figure 8). When the brush rod is started upwardly on its preliminary movement friction between brush 33 and the brush rod causes bell-crank 3l to be rotated as illustrated in Figure 8a. When the brush rod is stopped the brush 33 allows bell-crank 3l to return to its normal position in which pin 34 intercepts the path of' the trigger.

Following the preliminary movement one of the triggers is stopped just below the normal position of the pin 34 with which it is associated, as shown in Figure 8b. Upon the beginning of the secondary movement this trigger is engaged by pin 34 as shown in Figure 8 and the brush set is tripped.

If, following the preliminary movement, a trigger is stopped above its associated pin 34 or at a point somewhat lower than that illustrated in Figure 8h it will not be tripped on the secondary movement of the brush rod. In the latter case pin 34 will have been moved out of the path of the trigger before the latter is raised a sufficient distance to be engaged thereby.

The three embodiments of the invention set forth all come within the scope of a common underlying principle and they are all accordingly covered b-y the broad claims.

What is claimed is:

1. In a switch, a row of fixed contact terminals, a brush set adapted to be moved over said terminals, means for moving said brush set, means for normally holding said brush set non-operative relative to said terminals, during the movement of said brush set thereover. a tripping device comprising a pivoted member arranged to swing as a pendulum and adapted to effect a release of said brush set whereby the latter will engage said fixed ontact terminals` said last mentioned means being effective only when said brush set is stopped at a pre-determined position following said preliminary movement.

2. In a switch.y a row of fixed contact terminals, a brush set arranged to move over said terminals, means for moving said brush set, a device movable with said brush set adapted to normally maintain said brush set out of engagement with said terminals, a self-restoring tripping mechanism adapted to engage said device when said brush set is stopped in a predetermined position following a preliminary movement of said brush set, said tripping mechanism when so engaged with said devi being adapted to trip the latter in response to a secondary movement of said brush set thereby effecting engagement between said brush set and said terminals.

3. In a switch, a row of fixed Contact ter minals,` a brush set arranged to move over said terminals, means for moving said brush set, a tripping deviceV including a trigger movable with said brush set and adapted to normally maintain said brush set out of engagement with said terminals. and a pivoted member situated in the normal path of said trigger, said pivoted member adapted to swing out of said path in response to a preliminary movement of said trigger and to thereafter swing back into said path, said pivoted member being adapted upon swinging back into said path to engage said trigger when the latter is stopped in a predetermined position followingsaid preliminary movement, said engagement being effective to engage said brush set with said terminals upon a secondary movement of said brush set.

4. In a switch, a row of fixed contact terminals, a brush set arranged to move over said terminals, means for moving said brush set, a mechanism movable with and adapted to normally maintain said brush set out of engagement with said terminals, a trigger for said mechanism, a tripping device comprising a pivoted member arranged to swing as a pendulum, said tripping device having a surface angular to and normally in the path of movement of said trigger, and a detent in said trippin device adapted to engage said trigger w en the latter is stopped in juxtaposition to the normal position of said detent, said tripping device being arranged to swing out of its normal position in response to an engagement between said angular surface and said trigger upon a preliminary movement of the latter and to swing back to its normal position to engage said trigger when the latter is stopped in juxtaposition to said dctent following said preliminary movement.

5. An automatic switch comprisingr a movable shaft, a plurality of brushes resiliently secured thereto, controlling means individual to each brush for normally retain* ing said brushes in an inoperative position, a tripping device arranged to cooperate with each controlling means, means to successively actuate said tripping devices during the advance of said brush shaft, and means to release in operative position a desired one of said brushes by the joint action. of the tripping device and controlling means as a result of continued motion of said brush shaft the continued movement being in the same direction as the preceding movement.

6; An automatic switch Comprising a: movbie shaft, a piumfity of `hr'us'lies Se rured thereto, controlling means individual to ech brush for nol'm'allfy'reteling said brushes in inopeative condition; a tripping zone for eaer brush, meafns tfo' successively advance ,said brushes through said tripping zones and devices controlled in accordance with the time required for' a:- blfushl to pass throwgli a tripping zone' to' selectivey renf:

defsaid brushes operative.

7. In ai switch, fixed' contact enfniii's, a

brush set arranged' t'o move over said terminala means for moving Sid brush eet. a.' tripping device' movable with seid brush setfo'r controlling engagement of bhe brushes with said terminals, a, trigger adapted to be' moved out of ripping position by said brush set, and Ineens independent of said brush' set for restoring said trigger.

In Witness whereof I hereunto subscribe my nafme this 26th da'y of November. A. D.

LEE R. W ALLER. 

